Chinese news site Sina reported that the event had taken place in Hong Kong in the presence of Ng and Sze’s families and lawyers.
The couple is now preparing for their wedding ceremony, which is reportedly set to take place in Europe next August.
While appearing on a TV program in November, Sze revealed that he had made a will a few years ago, in which he stated that he would let Ng inherit the majority of his assets. He said he considered Ng someone that has a keen eye on investment, so he felt assured leaving his properties to her.
Ng, 30, is a model and actress. She began her career in the entertainment industry in 2010, and made her screen debut a year later.
Sze, 33, is the vice president of a digital payment platform. He graduated from the George Washington University in the U.S.
His grandfather and father are renowned businessmen, with his family’s net worth reaching HKD10 billion (US$1.28 billion), according to reports by the Chinese media.